The present invention relates to a vibrating pump with an isolated compression chamber, comprising a plunger as a compression/driving means, alternately moved by a magnetic system constituted by an electromagnet, in which said plunger pumps the liquid in a compression chamber from an inlet to an outlet. The vibrating pump of this invention has features designed to reduce the risk of leakage from the compression chamber to the force chamber and at the same time to increase the efficiency in the transformation of the electromagnetic energy into hydraulic energy of this type of pumps. The improvements concern the magnetic core/plunger assembly and the configuration of the compression chamber, which allows to obtain better results than the current pumps with less copper and to reduce the consumption of electric energy during its operation.
Various pressure pumps are known and used to moving liquids from one point to another, for example gear pumps, centrifugal pumps, vane pumps, vibratory pumps, etc.
The piston or membrane vibratory pumps, which are of the type to which the present invention relates, have an operation based on alternately displacing a magnetic core with the use of an electromagnet disposed around said core. The use of an alternative electric power generates magnetic pulses that cause the magnetic core to tend to be centered within the magnetic field produced by the electromagnet and a back-positioned spring fulfills the function of moving the magnetic core back again from this magnetic position of equilibrium producing the alternative movement of the magnetic core and the pumping work.
The magnetic and hydraulic system used by isolated chamber vibrating pumps of the type mentioned in DE102007007297 and U201400676 can have their efficiency improved and this is due to the failure of taking advantage of all the opportunities presented by this hydraulic-magnetic configuration, such as to reduce the friction load of the o-rings over the plunger.
The above-mentioned isolated chamber pumps need excellent sealing of the compression chamber to prevent water leakages to the magnetic system. A high load of the seal elements is necessary to achieve this degree of tightness over the plunger, o-rings for example, and the plunger moves at high speeds relative to said seals. Increasing the load of the seals over the plunger also increases the brake effect to its alternative movement and requires a greater magnetic force to move it resulting in more copper used in the coil. In today's isolated chamber pumps, reducing the seal load to the lower limit for achieve less friction and therefore lowering the copper amount in the coil is not possible because during work the water that would inevitably leak from the compression chamber would end in the force chamber or on the outside of the pump.
Even in the scenario where water leakage is compatible with the pump application, this alternative of reducing this seal load to reduce pump-manufacturing costs requires other collateral costs such as means for directing said water leakages away of the electrical parts of both the pump and the appliance that uses the pump. A further disadvantage of minimizing the sealing load is aesthetic as these water losses must be led to evaporation vessels to prevent them from coming out of the appliance and being perceived by the end customer.
Another important element in this sensible balance between the pressure exerted by the seals and the risk of water leakage is the material of the plunger on which these sealing seals work. Two factors affect this equilibrium: a—the change of diameter of the plunger with the humidity and/or temperature and b—the finishing of the plunger's surface. The modification of the diameter of the plunger alters the relative load of the seals and therefore increases the magnetic force necessary to move it or increases the leaks in the opposite case. The roughness of the plunger determines the life expectancy of the seals and consequently affects the lead-time to observe the first leaks and the quantity of water leaked. In order to keep these variables under control the selection of the material used for manufacturing the plunger is of vital relevance, the objective being to use a material that allows an excellent surface finishing and that does not modify its dimensions under the effects of temperature and humidity.
Therefore, the technical problem that arises is the introduction of substantial improvements to current isolated chamber pumps, thus solving some of the implicit drawbacks of this pumping technology while reducing material costs, mainly copper and steel, and manufacturing.